Fascioloides magna--epizootiology in a deer farm in Germany.

After initial observations of suspicious cases in 2009, the occurrence of Fascioloides (F.) magna in deer of a deer farm located in northeastern Bavaria, Germany, at the border to the Czech Republic was confirmed in autumn 2011. In March 2012, the deer were treated for fascioloidosis with triclabendazole. To monitor the epizootiology of fascioloidosis in the farm, 80-100 faecal samples were examined for Fascioloides eggs at monthly intervals from June 2012 to June 2013 inclusive. In addition, livers of 27 red deer and one sika deer collected during winter 2012/2013 were examined for gross lesions suspicious for F. magna infection and 21 of the 28 livers were dissected for F. magna recovery. Fascioloides eggs were recorded in 63 (4.9%) of 1280 faecal samples (range 0.4 to 355 eggs per gram). Both, number of Fascioloides-egg positive samples and egg counts were low during the first eight months of the study but increased notably since February 2013. While Fascioloides egg-positive faecal samples were obtained from red deer (46/948,4.9%) and fallow deer (17/166, 10.2%), no Fascioloides eggs were demonstrated in the 166 samples obtained from sika deer. Livers of five red deer and the sika deer showed gross lesions characteristic for fascioloidosis, and F. magna were recovered from three of the five affected red deer livers (range, five to seven flukes). Results of this study confirm that F. magna is endemic in the deer farm, and measures should be implemented to minimize the transmission of the parasite.